lkml.org 
[lkml]   [2012]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 069/187] ASoC: tlv320aic3x: Fix codec pll configure bug
Date
From: Greg KH <gregkh@linuxfoundation.org>

3.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: "Hebbar, Gururaja" <gururaja.hebbar@ti.com>

commit c9fe573a6584034670c1a55ee8162d623519cbbf upstream.

In sound/soc/codecs/tlv320aic3x.c

data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG);
snd_soc_write(codec, AIC3X_PLL_PROGA_REG,
data | (pll_p << PLLP_SHIFT));

In the above code, pll-p value is OR'ed with previous value without
clearing it. Bug is not seen if pll-p value doesn't change across
Sampling frequency.

However on some platforms (like AM335x EVM-SK), pll-p may have different
values across different sampling frequencies. In such case, above code
configures the pll with a wrong value.
Because of this bug, when a audio stream is played with pll value
different from previous stream, audio is heard as differently(like its
stretched).

Signed-off-by: Hebbar, Gururaja <gururaja.hebbar@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/soc/codecs/tlv320aic3x.c | 4 +---
sound/soc/codecs/tlv320aic3x.h | 1 +
2 files changed, 2 insertions(+), 3 deletions(-)

--- a/sound/soc/codecs/tlv320aic3x.c
+++ b/sound/soc/codecs/tlv320aic3x.c
@@ -936,9 +936,7 @@ static int aic3x_hw_params(struct snd_pc
}

found:
- data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG);
- snd_soc_write(codec, AIC3X_PLL_PROGA_REG,
- data | (pll_p << PLLP_SHIFT));
+ snd_soc_update_bits(codec, AIC3X_PLL_PROGA_REG, PLLP_MASK, pll_p);
snd_soc_write(codec, AIC3X_OVRF_STATUS_AND_PLLR_REG,
pll_r << PLLR_SHIFT);
snd_soc_write(codec, AIC3X_PLL_PROGB_REG, pll_j << PLLJ_SHIFT);
--- a/sound/soc/codecs/tlv320aic3x.h
+++ b/sound/soc/codecs/tlv320aic3x.h
@@ -166,6 +166,7 @@

/* PLL registers bitfields */
#define PLLP_SHIFT 0
+#define PLLP_MASK 7
#define PLLQ_SHIFT 3
#define PLLR_SHIFT 0
#define PLLJ_SHIFT 2



\
 
 \ /
  Last update: 2012-07-13 05:43    [W:0.454 / U:17.916 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site